- changed "for_update" parameter to accept False/True/"nowait"

and "read", the latter two of which are interpreted only by
Oracle and Mysql [ticket:292]
- added "lockmode" argument to base Query select/get functions,
including "with_lockmode" function to get a Query copy that has
a default locking mode.  Will translate "read"/"update"
arguments into a for_update argument on the select side.
[ticket:292]

1 files changed, 8 insertions, 6 deletions

diff --git a/lib/sqlalchemy/ansisql.py b/lib/sqlalchemy/ansisql.py
index c44595f36..66b917c20 100644
--- a/lib/sqlalchemy/ansisql.py
+++ b/lib/sqlalchemy/ansisql.py
@@ -394,13 +394,9 @@ class ANSICompiler(sql.Compiled):
             text += " ORDER BY " + order_by
 
         text += self.visit_select_postclauses(select)
- 
-        if select.for_update:
-            text += " FOR UPDATE"
 
-        if select.nowait:
-            text += " NOWAIT"
-            
+        text += self.for_update_clause(select)
+
         if getattr(select, 'parens', False):
             self.strings[select] = "(" + text + ")"
         else:
@@ -415,6 +411,12 @@ class ANSICompiler(sql.Compiled):
         """ called when building a SELECT statement, position is after all other SELECT clauses. Most DB syntaxes put LIMIT/OFFSET here """
         return (select.limit or select.offset) and self.limit_clause(select) or ""
 
+    def for_update_clause(self, select):
+        if select.for_update:
+            return " FOR UPDATE"
+        else:
+            return ""
+
     def limit_clause(self, select):
         text = ""
         if select.limit is not None: